HSR Carburetor
Total Kits Installation Instructions HSR42 Kits: #42-8 #42-19
’84 - ’99 Evo Big Twin ’99 - present Twin Cam
#45-2 #45-3 #45-4
’84 - ’99 Evo Big Twin ’84 - ’99 Evo Big Twin ’99 - present Twin Cam
HSR45 Kits:
Revised 01/22/02
TK-1
Total Kit Installation Instructions The HSR series carburetors are precise yet durable instruments; however, like any other piece of ne equipment, they require correct installation and reasonable care to assure optimum performance and long life. Extra time spent during installation will pay off in both shor t and long term performance and reliability. This Mikuni HSR carburetor kit is designed to be a bolt-on appli cation, and as such, is set-up and jetted properl y for most applications. However, since Harley-Davidson motors are often highly modied, alternate tuning settings may be required. The Mikuni Tuning Manual helps make jetting alterations and adj ustments an easy matter. NOTE: Carburetor Kits not designated as C.A.R.B. exempt, are not legal for motor vehicles operated on public highways in the state of California, or in any other states and countries where similar laws apply.
Notes, Cautions and Warnings:
Disassembly:
Statements in this manual preceded by these words are very important:
1. 2. 3. 4.
NOTE:
Gives helpful information that can make a job easie r.
CAUTION Indicates a possibility of damage to vehicle if instructions are not followed.
WARNING Indicates a possibility of personal injury or vehicle damage if instructions are not followed.
Disconnect the battery ground wire from the battery. Turn the fuel petcock to the “OFF” position. Elevate the rear of the tank for better access. Remove the coil, horn or other devices on the left side of the engine to gain access to the manifold bolts. 5. Remove the complete air cleaner assembly. 6. Disconnect any vacuum hoses and the fuel hose from the stock carburetor. 7. Disconnect the choke cable from the frame. 8. Remove the stock carburetor. 9. Evo: remove the stock manifold. 10. Twin Cam: unplug MAP sensor, remove manifold and then remove the MAP sensor from the manifold.
Installation: NOTE:
WARNING Read these instructions carefully before you begin installation of your HSR kit. All procedures in this manual should be followed, paying particular attention to the following: 1. 2.
3. 4.
Mikuni HSR series carburetors require the use of a push/pull throttle assembly to assure closing of the throttle valve. The throttle cables should be routed freely (without sharp bends) between the throttle twist grip and the carburetor and must not be pinched. Gasoline is extremely ammable and is explosive under certain conditions. Do not install your Mikuni near open ame. Never look directly into the bore of the carburetor while the engine is running as injur y may result from possible backre.
Lubricate the manifold seals (liquid soap, oil or grease).
Intake Manifold: 1. Install MAP sensor in Mikuni manifold (Twin Cam only). 2. Attach the Mikuni manifold to the engine. Align the manifold before tightening the bolts. The ange surface of the Mikuni manifold should be parallel with the front of the engine’s cam cover. Use a level or angle meter to check this. Tighten the manifold bolts. 3. Attach the rubber ange to the Mikuni manifold with the furnished 5/16”x3/4” bolts and washers.
Choke Cables: Mikuni & Harley-Davidson NOTE:
NOTE:
The Mikuni intake manifold, included in these kits, requires the anges and seals from a ’90 and later “Big Twin.” If you do not have these parts, you will need to get them from a Har leyDavidson dealer. The required par t numbers are: 1. 27009-86A Flange 1 ea. 2. 27010-86A Flange 1 ea. 3. 26995-86B Seal 2 ea.
Route the cable with largest radius bends possible. Check the cable for free-play after installation. If there is no free-play, the engine may run rich and deliver poor performance or low fuel mileage.
Harley Cable (Twin Cam Kits: 42-19, 45-4) : 1. Remove the Harley choke cable from the stock carb. 2. Remove the spring and plunger from the cable. 3. Remove the spring and plunger from the Mikuni. 5. Install the Mikuni spring and plunger onto the Harley choke cable. Change nothing else; be sure to use the Harley plastic nut, not the Mikuni nut (See Figure 1).
TK-2 6. Install the new assembly into the Mikuni carburetor. Be careful to only gently tighten the plastic nut. 7. Loosen the knurled plastic friction nut behind the choke knob and check for free-play (see Figure 2).
5. Adjust the opening cable until the slide can be opened fully. Snug the adjuster lock nut. 6. Turn the handlebar to the right and adjust the throttle free-play with the closing cable adjuster to approximately 1/8” (see Figure 4).
WARNING Figure 1: Harley nut with Mikuni spring & plunger
The control cables must not pull tight when the handlebar is turned fully left and right. Also, be sure that the cables clear the fork stops at the steering head so they are not pinched when the handlebar is turned. There must be some free-play at all handlebar positions to avoid binding in the throttle cables. Binding causes excessive wear and interferes with precise throttle control.
Figure 2: Choke cable adjustments Figure 3: Cable installation guide
Mikuni Cable (Evo Kits: 42-8, 45-2 & 45-3) : 1. Remove nut, spring and plunger from the Mikuni. 2. Install the nut, spring and plunger onto the cable. 3. Install the assembly into the Mikuni HSR carburetor. Be careful to only gently tighten the plastic nut. 4. Check for free-play. Adjust the cable as necessary. NOTE:
An optional choke cable mounting bracket is included in the Evo kits for custom installations.
Carburetor Installation: 1. 2.
Insert the carb fully into the rubber ange, align with engine and tighten the clamp. Slip the fuel hose onto the carburetor’s fuel tting and secure with the enclosed hose clamp.
Figure 4: Throttle free-play
Cable Lube: Remove upper throttle housing and lube each cable.
NOTE:
Some Twin Cam installations may require removal of a small amount of n material from the cylinders to clear the oat bowl.
Throttle Cables The HSR carburetor uses stock 1990 and later HarleyDavidson cables. However, if your Harley is tted with some other carburetor, you may need to purchase a set of cables. See your dealer for the correct cable set. 1. Route the throttle cables with large radius curves and so they do not interfere with other components. 2. Screw the cable adjusters together to make them as short as possible. 3. Connect the “close” cable rst (see Figure 3). 4. Install the “open” cable next (see Figure 3).
Figure 5: Cable lube procedure CAUTION Cable lubrication is important. Dry cables can result in sticky throttle action, slow return to idle and excessive cable wear.
TK-3 Air Cleaner and Breather:
Air Cleaner Element Care:
Use the supplied brackets, breather kit parts, O-rings, bolts & washers as required. See illustrations below.
Inspect and, if necessar y, clean the air lter every 5,000 miles. The K&N brand lter supplied with this kit is very effective. It removes extremely small dirt par ticles yet does not substantially interfere with air ow into the engine. When you clean the lter, be sure to follow the cleaning instructions included with this kit.
Evo Engines: KHS-020 breather kit ’84-’91: Use 2 ea. 5/16”x3/4” bolts, washers and O-rings. ’92: Use 2 ea. 1/2”x3/4” bolts and at washers. ’93-’99: Add the included breather kit (KHS-020). TwinCam: KHS-030 breather kit. 1. Loosely attach the brackets and/or breather parts to the cylinder heads with the appropri ate hardware. 2. Remove the rubber stud protectors from the Mikuni air lter and place the two backing plates on the studs. Position the air lter up to the carburetor while aligning the brackets with the lter studs. Once the lter is in place, tighten the lter clamp. Then, secure the lter to the brackets with the enclosed 5/16” nuts and at washers (see Figure 9). 3. Cut out the thin membranes in the back of the lter and insert the plastic elbows. Use the 5/16” i.d. hose to connect the elbows to the breather ttings. 4. Use the stock cover screw to attach the Mikuni air cleaner cover to the air lter.
Hose Routing: 1. Use the kit’s hose clamps to secure the fuel hose to the petcock and carburetor. Fit the screw clamp to the petcock end and the spring clamp to the carb. 2. Evo: Fit the V.O.E.S. or petcock hose to the carburetor. A piece of vacuum hose is included in the kit 3. Twin Cam: Attach the petcock vacuum hose to the carburetor. 4. Route the oat bowl overow hose below the engine. Do not connect this hose to any other hoses.
Figure 6: Air cleaner assembly guide
CAUTION 1.
If you are not using the V.O.E.S., seal the Vacuum Fitting on the carburetor. 2. The Vent Fitting located above the Fuel Fitting must not be sealed! Sealing it results in erratic air/fuel mixture ratios, poor performance and possible engine damage.
NOTE:
You may have some hoses remaining after your installation. Since this is a performance application only, some hoses and related hardware may no longer be required.
Starting: Re-connect the battery and re-assemble the remainder of the motorcycle. Turn the petcock on and start the engine as you normally would (be sure the throttle is fully closed). After it is warm, set the idle to the recommended 1,000 to 1,100 r pm. To learn more about adjusting your HSR carburetor, refer to the included Tuning Manual.
Figure 7: ’84 – ’92 breather installation
TK-4
Kit Contents: Twin Cam:
Figure 8: ’93 – ’99 Evo breather (KHS-020)
TM42-6 TM45-2 HS42/012 HS42/012-300 HS42/02-250-CHR HS42/061-45TC HS42/062-42 HS42/062-45 KHS-030 N100.604-155 N100.604-165 N100.604-170 N100.604-180 RS36/47 Z70/042 Z70/045 Z70/05512 Z70/146 HS42/073 RS36/27-075
Evo:
Figure 9: Twin Cam breather (KHS-030)
TM42-6 TM45-2 HS42/012 HS42/012-300 HS42/019 HS42/021-250-CHR HS42/034 HS42/037 HS42/038 HS42/061-45 HS42/062-42 HS42/062-45 KHS-020 N100.604-155 N100.604-165 N100.604-170 N100.604-180 RS36/02-17 RS36/23 RS36/27-075 RS36/28 RS36/3609 RS36/37 RS36/47 RS36/54 Z70/042 Z70/045 Z70/05512 Z70/146 990-662-002 HS42/073
Kit: 42-19 45-4 Carburetor Carburetor Air Filter, 2-1/2” Air Filter, 3” Cover A/C (Chrome) Manifold Rubber Flange Rubber Flange Breather Kit Main Jet Main Jet Main Jet Main Jet Plate, Back Flat Washer, 5/16” Hose Clamp Hose, Fuel Nylon Cable Tie Cable Lube Bolt, Hex 5/16”x3/4”
1 1 1 1 1 1 1 1 1
2 2 1 1 4 1 2
1 1 1 1 1
1 1 2 2 1 1 4 1 2
Kit: 42-8 45-2 Carburetor Carburetor Air Filter, 2-1/2” Air Filter, 3” Bracket, Air Filter Cover A/C O-ring Bolt, 1/2”-13 x 1” 1/2” Washer Manifold Rubber Flange Rubber Flange Breather Kit Main Jet Main Jet Main Jet Main Jet Hose Clamp Choke Bracket Bolt, 5/16” x 3/4” Nut, 5/16” Hose, 3/16” x 9” Elbow, Plastic, 3/8” Plate, Back Screw, Cover Flat Washer, 5/16” Hose Clamp Hose, Fuel Cable Tie, 7-1/2” Choke Cable Assy Cable Lube
1 1 1 2 1 4 2 2 1 1 1 1 1
1 1 4 2 1 2 2 1 6 1 1 4 1 1
1 2 1 4 2 2 1 1 1
1 1 1 1 4 2 1 2 2 1 6 1 1 4 1 1
Note: The 45-3 Kit does not include a manifold. Otherwise, it is identical to the 45-2 Kit.
TK-5
# PART NO. 1. C5=0410-B 2. CW2=0414-B 3. 776-39005 4. TM42/04 5. BS32/126 6. 826-03002 7. J8-8DDY01-97 7a. J8-8CFY02-97 8. TM42/03 8a. TM42/08-1A 9. B40I/56 10. B40I/10 11. 834-23041 12. TM42/08-3.0 13. 739-13002 14. TM42/16 15. TM42/13 15a. TM48/02 16. TM42/10 17. 925-98006 18. 53974 19. TM42/51 19a. TM42/53 20. B3=0520-B 21. VM28/204 22. TM42/38 23. C2=0514-B 24. 640-12001 25. VM14/241 26. N189.192 27. TM42/06 27a. TM48/02 28. 616-94029 29. 925-19011 30. TM42/43 31. N138.019 32. TM42/48 33. M12F/46-BB 34. MC-0316-B 35. TM42/47 36. TM42SS1/01-0 36a. TM48SS1/01 37. B36/95 38. TM42/36 39. B30/205 40. TM40/89 40a. TM42/17 41. BN38/43 42. TM42/46 43. B30/1069 44. N3=04 45. TM42/19 46. 700-15012 47. TM42/15 48. C2=0410-B 49. 604-26014 50. N133.206
HSR PARTS LIST
DESCRIPTION Screw, Top Cover Screw, Top Cover Top Cover Gasket, Top Cover E-Ring, Jet Needle Washer, Jet Needle Jet Needle (42) Jet Needle (45/48) Lever, T.V. (42/45) Lever, T.V. (48) E-Ring, Link Lever Packing, Link Lever Pin, Link Lever Throttle Valve (Slide) Screw, Needle Retainer Clip, Needle Retainer Sealing Ring, T.V. (42/45) Sealing Ring, T.V. (48) Seal, Throttle Valve Pulley, Cable Bracket E-Ring, Cable Bracket Bracket Ass’y, Cable Bracket Ass’y, Sportster Bolt, Bracket Spacer, Bracket Plate, Lock Tab Screw Starter Nut, Choke Spring, Starter Plunger Starter Plunger Body, Bearing & Spigot (42/45) Body, Bearing & Spigot (48) Seal, Spigot Body Ring (Steel) Lever, A/P Pin, Throttle Lever Lever, Throttle Spring, A/P Screw, A/P Spring, A/P Mixing Body (42/45) Mixing Body (48) Packing, Shaft (Plastic) Adjusting Screw, A/P O-Ring, A/P Screw Bolt Plate, Lock Tab for Shaft Pin, Return Lever Lever, Return Adjusting Screw, Throttle Nut, Throttle Stop Spring, Throttle Return Shaft, Throttle Plate, Fuel Joint Retainer Screw, Fuel Joint Screw, Pilot Air Spring, Pilot Air
51. VM12/205 52. N133.037 53. TM40/27 54. KV/10 55. B30/398 56. VM22/138 57. 730-09018 58. 925-15001 59. TM42/32 59a. 990-605-065 60. BS30/97-00 61. 784-430000-Y-6 62. TM42/11-70 63. N124.063 64. VM28/486-25 65. TM42/12 65a. TM42/12-1A 66. N100.604-160 67. 616-33003 68. VM13/216 69. 786-27001-4.2 69a. 786-27002-1A 70. 859-32027 71. BV26/22 72. C2=0410 73. 616-94028 74. TM42/05 75. N122.028 76. VM28/254 77. TM32/41 77a. TM32/41-1D 78. C2=0412-B 79. TM36/44-1A 80. TM36/64 81. TM36/60 82. VM14SC13/89 83. N198.063
Washer, Pilot Air O-Ring, Pilot Air Fuel Joint O-Ring, Fuel Joint Packing, Idle Adjuster Washer, Idle Adjuster Spring, Idle Adjuster Ring,Idle Adjuster Idle Adjuster (Long) Idle Adjuster (Short) Air Jet (Blank) Needle Jet (723) Nozzle, Accel. Pump O-Ring, A/P Pilot Jet Extender, Main Jet (42/45) Extender, Main Jet (48) Main Jet O-Ring N.V. Screw, N.V. Retainer Needle Valve Ass’y (42/45) Needle Valve Ass’y (48) Float Ass’y Pin, Float Screw, Float Pin Packing, Float Bowl Float, Chamber Body Hose, Overow O-Ring, Drain Plug Drain plug (42/45) Drain Plug (48) Screw, Flt Bowl, short Rod, A/P Boot, A/P Rod Plunger, A/P Spring, A/P Rubber Cap, Purge Port
Alternate Parts Jet Needles: HSR42 HSR45/48 J8-8DDY01-95 J8-8CFY02-95 Richer J8-8DDY01-96 J8-8CFY02-96 Richer J8-8DDY01-97 J8-8CFY02-97 Std J8-8DDY01-98 J8-8CFY02-98 Leaner Accelerator Pump Nozzles: TM42/11-70 Std TM42/11-60 Leaner TM42/11-50 Leaner Needle Valve Assemblies: 786-27002-1A-4.5 Std (HSR48) 786-27001-4.2 Std (HSR42/45) 786-27001-3.5 Smaller 786-27001-2.3 Pressure only NOTE: Rebuild Kit: HSR42/45: KHS-016 HSR48: KHS-031
1. Lined through part numbers are not available. 2. Parts in bold are included in rebuild kits.
TK-6
TK-7
Mikuni American Corporation 8910 Mikuni Avenue Northridge, CA 91324-3496 www.mikuni.com
